1. Field
An embodiment of the invention relates to a disk device provided with an inertial latch mechanism for a head actuator and a manufacturing method for the disk device.
2. Description of the Related Art
In recent years, magnetic disk devices, for example, have been widely used as large-capacity disk devices for electronic apparatuses such as personal computers. In general, a magnetic disk device comprises a magnetic disk, spindle motor, head actuator, voice coil motor (VCM), board unit, etc., which are located in a case. The spindle motor supports and rotates the magnetic disk. The head actuator supports a magnetic head. The VCM, which serves to drive the head actuator, includes a voice coil attached to the head actuator, a pair of yokes mounted on the case side, and a permanent magnet.
Further, small-sized portable personal computers have recently been spreading, and magnetic disk devices that are mounted on the personal computers of this type are expected to be improved in reliability against a shock or the like that may be produced while the computer is being carried about.
Thereupon, a magnetic disk device is proposed that comprises a ramp load mechanism as a mechanism for holding the magnetic head in a predetermined position when the device is non-operating. This ramp load mechanism is provided with a ramp that is located outside the magnetic disk. When the disk device is non-operating, the head actuator is rocked to a retracted position beside the outer periphery of the disk, whereupon a suspension runs onto the ramp. Thus, the magnetic head is held in the retracted position off a surface of the magnetic disk, so that it can be prevented from colliding with the disk when subjected to a shock.
Furthermore, one such magnetic disk device is proposed having an inertial latch mechanism that enhances its shock resistance. If a shock acts on the magnetic disk device in a non-operating state, the inertial latch mechanism engages the head actuator to restrict its rocking motion, thereby holding the head actuator in the retracted position.
As disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2003-51165, for example, the inertial latch mechanism has an inertial arm and a latch arm. The inertial arm is rotated in both forward and reverse directions by external shock acceleration. The latch arm is urged to rotate in one direction as the inertial arm rotates. If a shock is produced in the non-operating state, the latch arm engages the head actuator, thereby holding the head actuator in the retracted position.
In the inertial latch mechanism constructed in this manner, the inertial arm and the latch arm are supported individually by pivots for rotation that are set up on a bottom wall of the case. With the recent miniaturization of magnetic disk devices, the case has been reduced in size and thickness. It is difficult to set up the pivots on the thin bottom wall.
As the magnetic disk devices have thus been reduced in size, the inertial arm and the latch arm of the inertial latch mechanism have become very small components. In assembling the magnetic disk devices, it is very troublesome to mount those small components on the pivots that are set up on the case in which various parts are incorporated, so that the working efficiency is low.